Turbines have established a wide usefulness as prime movers, and are manufactured in many different forms and arrangements. They are used to drive many different types of apparatuses, e.g., electric generators, pumps, and compressors. Turbines have also been used in high speed spin test system for the testing of critical components used in rotating machinery.
A typical design of a turbine comprises a stationary set of blades, often called nozzles or stationary air foil vane, and a moving set adjacent thereto, called rotor buckets, or rotor blades. These stationary and rotating blades act together to direct steam or pressurized air to do work on the rotor. The work can be transmitted to a load through the shaft or spindle on which the rotor assembly is carried. Thus, the only parts that rub and wear are the bearings which support the rotor blades.
In a typical impulse turbines, the annulus following the nozzle exit is filled with steam or air flowing with a high velocity tangent to the rotor. The entire pressure drop is taken across the stationary air foil vanes.